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Sturgeon's House


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Posts posted by Xoon

  1. 58 minutes ago, N-L-M said:

    If that's what you feel best suits the needs of the Lone Free State, go for it.

    I am just joking.

    I am guessing the practical limit is 40 ton, since more than 4 axles are rare on AFVs.





    Bilderesultater for Heavy mobile crane


    I am going to laugh my ass off if this ends up being the winning submisson, just replace the crane with a cannon.

  2. 18 hours ago, Gripen287 said:


    I'm no expert, but according to wikipedia , this drawing is incomplete. Wikipedia says this is, " [a] Differential steering mechanism, either double-differential minus the clutches, or triple-differential minus the brakes. 


    More specifically, I believe they mean a Maybach double differential with clutches to disconnect the "slowed" (i.e., not sped up) sprocket when steering torque is applied. Alternatively, the diagram could depict an "ordinary" double differential transmission, but the diagram's "epicyclic gears" are not correctly drawn as differentials, as in the transmissions depicted here or here. To depict a triple differential transmission, the steering torque is input into the steering half shafts via yet another, third differential (the diagram is missing a carrier having idler(s) between the steering half shafts) and brakes and/or clutches on the steering half shafts selectively engage and/or disengage to effect a steer. If you haven't already, you might want to revisit Coli's link.


    So, yes, you are correct in that the diagram does not include means for controlling the reactive torque applied to the drive input by the slowed sprocket when the steering input is driven. If the drive input and steering input were independently driven, you might be able to get away with that kind of set up for a while, maybe.... But the various multi-differential transmissions differ, more or less, in how to address the issues you have raised. 

    Thank you, this cleared up a lot of things for me. 


    I have been looking into torque vectoring transmissions and differential steering for electric and hybrid transmissions. 


    I saw the transmission made by University of Munich:





    Here is another one from Borg Warner:




    Call me a idiot or something, but I can't for the love of god understand these. It can't be as simple as using a electric motor and a clutch to apply additional power to one of the two wheels right? 


    I have also been pondering about the efficiency of several transmissions, and I honestly came to the conclusion  from rough estimates that a dual motor setup is the most optimal. 


    Let's consider a few layouts:
    -Single motor with a differential.

    -Independent motor setup.

    - Double differential with electric motors.


    In a single motor setup with a transmission, one would think one motor would be more efficient right? Well, actually no, as seen in many hyper efficiency EVs.


    Let's have a few basis numbers:
    Electric motor(M): 95%

    Motor controller(C): 95%

    Differential(D): 93%

    Reduction gear(R): 95%
    Power(P): 100Kw


    Single motor with differential:
    Efficiency = (P*C*M*R*D)

    79,93% = (100*0,95*0,95*0,95*0,93)


    Total system efficiency is 79,93%.

    Capable of basic torque vectoring with braking, greatly hurting the overall efficiency.


    Independent motor setup:
    Efficiency = ((P/2)*C*M*R)*2

    85,74% = ((100/2)*0,95*0,95*0,95)*2


    Total system efficiency is 85,74%.


    Honestly, considering the complicated gearing, gearing of the double differential system with electric motors, I doubt it would come close to either above, so I will do any rough calculations. 



    A independent motor setup also beats out a average transmission by 10 percentage points. (85% vs 75%). Factoring in the generator and rectifier (0,95 for generator and 0,95 for active rectifier) it still leads by 5% points (80% vs 75%). 

    This might not seem like a big deal, but this is essentially 75hp in a 1500hp system.  And this does not even start to factor in regeneration, which in EV's extend their range by up to 30%, and should be just as effective in a tank that frequently sprints and stops. 
    Not to mention the fuel saved by running the engine at a constant RPM, harvesting excess power from the turbocharger, and being able to automatically turn the engine on and off to save fuel while on standby, and the increased initial acceleration.  One could also saved weight, as there is no need for a starter, alternator or flywheel.  The internal generator could even be used to external equipment or high power equipment like a ETC gun.  1100Kw is a lot of power to have on standby. 


    Other advantages of the independent  motor setup, hereby IMS, is the ability to "reverse" the transmission. You can literally drive the same speed in forward as in reverse, and you could reuse a MBT chassis as a IFV chassis by turning it around, vice versa. 

    The motor can also be used for negative torque vectoring, recovering power when doing tighter brake turns. They can also produce peak power 3+ times their continues rating.  That means a 1000hp AFV would be able to do short sprints at 3000hp!


    It has been noted that it would not be able to transfer torque between the motors, but when does a AFV actually need to apply more than 50% power on one track? As far as I have seen, it is a rare occurrence. Another issue some say would be that the motors would rotate at different speeds.  This would be very easy to rectify. Simply use the motor controllers current readings (Sinus curve corresponds to the position of the rotor magnets in relation to the poles on the motor) to track the motor's rotor position and estimate the speed from that , or at a rotary encoder for a simply speedometer. 






  3. 440px-Differential_steering_mechanism.pn

    Could anyone with a good understand of gearboxes explain how this steering differential works?


    As far as I understand, the drive input powers the system, and when the steering differential's RPM equals zero, the torque is distributed equally.
    When the steering input rotates clockwise, the right side drive gets the most torque, proportional to the steering input torque. 

    When the steering input rotates counter clockwise, the left side drive gets the most torque, proportional to the steering input torque. 


    When the drive input is put in neutral, the steering input can be used to pivot on the spot. When doing this, the steering input directly powers the side drives. 


    The one thing I get is, how does the steering input control the torque of the drive side? Is it by the epicyclic gear? 

    Why does it not transfer the torque back into the steering input and grind against the other epicyclic gear, or fight the steering input?

  4. I have a few questions regarding US gun laws:


    Do US firearms come with a identification number that is registered to an owner, that the police can search up in a database?

    In that case, could police then do random check ups on people's firearms to check if the firearm has been stolen?

    In the case the registration number is gone, or scratched up, the police could confiscate the firearm, until the owner gets a new registration plate or re-registers the gun.

    This way, the US would know how many guns each person owns, and how many in total in the US. 

    A national fire arms register could be established, which could be checked with medical and police records of the owner and the house hold. 
    If the police see a mentally ill person stockpiling weapons commonly used by mass shooters, they could put them on a watch list.


    And what about a incentive for people to buy less "assault weapons" with either a tax on the more lethal weapons, or a discount on the more personal defense oriented firearms. 
    Let's say all small compact pistols with equal or less than 15 rounds in the magazine gets a 15% discount. 
    Or all hunting rifles that can contain more than 5 rounds have a 10% tax. 


    The idea would to instead of banning all sorts of useless things, we could incentivies people to buy less lethal and more practical weapons. Enthusiasts could still own their AR-15 with 200 round drum mag, with a bumpstock and night vision scope, while the average bloke would probably own a cheap and compact pistol for concealed carry in self defense. 



  5. 953ab796-008e-43f6-b749-dc742badd6e4?fit


    Apparently there was a attempted mass shooting in Bærum, Norway. 


    A guy armed with a shotgun and a pistol, plus some other guns shot up a Mosque, but luckily failed to kill anyone, and was subdued by a 75 year old man.

    He is now charged with attempted murder of three people. 


    He was a ethnically white Norwegian man in his early 20s. He has no previous notable crime record and lives in the same area as the Mosque. 
    He wore a NATO sweater (Norwegian army sweater) and a bullet proof vest. 
    The media really wanted to hammer in the fact that he was ethnically Norwegian and white.




  6. 2 hours ago, Zyklon said:

    I know you said it later already but to just to get the point across, electricity is pretty much the worst way to heat anything in the house , and you really only use it for retrofitting were nothing else would work or if your customer is a cheap bastard.


    If you really don´t want to use or have access or the space available for Wood, Gas or Oil, then atleast buy a heating pump, because depending on the type you can get COPs of around 4, which means for each unit of Electricity consumed you get 4 units of heat. Those nice heating pumps can also be put outside and they are not that loud, except you use Split-Systems were the fan is louder than your neighbouring airport.

    In the area, where I live, which is not more expensive compared to the rest of the country, the square meter price is roughly 3750 USD per square meter. This makes large houses expensive, so you want to use space as efficiently as possible. Electric floor heating is almost universally used only on bathrooms until recently, since they have tiles, which get very cold. Since the total watt usually roughly equals your average heater, and the very cheap power we have here, the electricity efficiency is not really a factor. 

    What is a huge factor, is installation cost. Adding a boiler, water pump, heating element, piping, valves and thermostats is very expensive, especially when the typical plumber costs 135USD an hour. Oil heating is now banned. You have the refill a gas tank, and store in in a safe area, which is a huge hassle. Wood is plenty and cheap, but requires frequent refilling and a lot of space, usually people opt for a fireplace instead. 
    Electric floor eating is relatively cheap. The construction worker simply lays it down into the floor before adding the concrete, and the electrician puts a temperature measure wire below the floor tile to the thermostat, while also wiring the thermostat. This requires 1 10A fuse, probably 20m of cable and a thermostat.

    Recent advances allows you to cut heating elements into size from rolls of fabric, and just lay it under the flooring. 


    Heating pumps are a very recent thing, and don't really work too well. They do provide cheaper heating, but cost a lot of initially install, and takes 20 years to pay off themselves.  This is because of very low temperatures in the winter and low electricity prices.  Ground heating fixes the cold issue, but is very expensive.


    Cooling is rarely a issue. Since it usually never gets hotter than 24 degrees C around here. Record was 32,4 degrees C. 


    Recently, heating all the floors as gotten more popular. But this is usually done when retrofitting old houses. Which is extremely expensive to do by water born heating.  



    If I get the money to build my own house, I'll probably build a house with water born heating, but most construction companies shy's away from it. 

  7. Nordic Feminist Design Division presents: P2055 “Gaupen”














    Table of basic statistics:



    Mass, combat

      65 metric ton

    Length, combat (transport)


    Width, combat (transport)


    Height, combat (transport)


    Ground Pressure, MMP (nominal)


    Estimated Speed


    Estimated range


    Crew, number (roles)

      2 (Commander, Gunner/Driver)

    Main armament, caliber (ammo count ready/stowed)

      200mm L40 gun. (40 rounds, 15 in first autoloader).

    Secondary armament, caliber (ammo count ready/stowed)

      7,62mm GPM (1200 rounds).


    12,7mm HMG (500 rounds)


    Vehicle designer’s notes:
    The P2250 was designed to be as heavily armored as possible, with the smallest weight and profile.  We tried to make use of the new experimental technologies and developed our own hydrostatic transmission and hydropneumatic suspension. This allowed much greater low speed mobility and some interesting arrangements. With the cannon mounted to the chassis, the autoloader became simplified and allowed a higher theoretical rate of fire and a reduction of crew to only 2. 


    1. Link to Appendix 1- Not realized because of lack of weight value. 


    2. Engine - Kharkov 5TD (increased to 6 cylinder), 16L, 800HP, water cooled, constant speed.


    3. Transmission - Hydrostatic, 1 Forward, 1 Neutral and 1 Reverse, engine forward; motor and controls in the rear, is a continuously variable transmission, allow the engine to run at a constant speed with instant torque. It features hydraulic breaking and locking on top of normal friction breaks, also has a minor regenerative capabilities.

    Location of drive train components and their connections:



    4.Fuel - Diesel, 1000L, sponsons, 400km, was planning to add optional fuel barrels for increased range, but scrapped because of time limit. 


    5. Powerpack is set up as an open circuit hydraulic system, allowing it to power auxiliary equipment and other subsystems like the auto loader and suspension, or power tools.


    6. Suspension- Hydropneumatic (Nitrogen), 500mm suspension travel, 500mm ground clearance. The suspension is a fully adjustable in arm suspension using a slider crank design. Each arm has a built in shock absorber and can be either electronically or manually adjusted. Each unit has an overpressure valve to limit damage to the unit during very rough travel. Each unit is a bolt on unit, making replacements easy and fast.


    View of the suspension:










    Red: Ammunition and cannon.
    Blue: Composite armor.
    Grey: Drive line components.
    Green: Fuel. 
    Brown: Crew. 



    1.     Link to Appendix 1 - Not realized. 

    2.     Link to Appendix 2- Not Realized,  has a 1000mm deep armor cavity at 1,79m^3 at the front, with a 900mm deep armor cavity at 180mm height on each sponsons. 


    3. Non-specified survivability features and other neat tricks-
    Very low profile vehicle with the ability to further reduce its profile by lowering its suspension. Very low profile while in hull down position.

    Has blow off panels, light panels that are screwed in place to break off when ammunition ignites.   Fuel is used as side armor. 




    A.    Weapons:


    1.     Link to Appendix 1- Not realized.


    2.     Main Weapon-


    a.      Smoothbore cannon (510 MPa working pressure). 


    b.      200mm caliber. 


    c.      Ammunition:
             Common: 200 x 900 mm brass case, estimated 50kg. 
             HEAT: Not realized. 

             HE: Not relied. 

             AP: Not realized. 



    d.     Ammo stowage arrangement- 15 rounds stored in primary shell conveyor, 25 rounds stored in secondary shell conveyor.  Entire system has blow off panels above it. The system is powered by the tanks hydraulic circuit. 



    B.    Optics:


    1.     Primary gunsight- two axis stabilized gunners sight.


    2.     Drivers 3 vison telescopes. Commander features 360 degree coverage form the copula with a 4x sight connected to the RCWS. 


    C.    FCS:


    1.     FCS- Gun is rigidly mounted to the chassis. The gunner can select a firing mode to put the vehicle into precision mode.  Tracks turn to traverse the cannon, and the suspension adjusts to elevate to depress the gun. The gunners controls feeds into the suspensions control system, modifying the pressure in each individual suspension unit to accomplish the right elevation/depression. A gyroscope keeps track of the vehicles tilt and adjusts accordingly.  
    The commanders station has duplicated controls and features a fully rotatable commanders copula with a range finder and 12,7mm remote operated HMG. The commander can measure the range and move the tank accordingly, giving a sort of hunter-killer system. 


    2.     Link to Appendix 3- May be added in the future. 




    1.     Ease of service and maintenance on the suspension units.

    2.     Low maintenance transmission, hydraulic motors do not require a lot of maintenance.

    3.     Reduced brake wear because of hydraulic parking break and minor regenerative breaking. 

    4.     Reduced engine wear from running on a stable RPM. 

    5.     It has a 200mm cannon. 

    6.     Has a remote controlled weapons station, allowing the commander to avoid peaking his head out when firing on infantry.


    Free expression zone:
    The Nordic Feminist Design Division felt that there was a sever lack of special needs armored fighting vehicles which strives against our glories republics values. 
    The team set out to make the most inclusive vehicle possible. The turret was quickly removed as it was seen as offensive to the crippled, gifted people of our republic.  Next was the issue with the height. The tank was too high to climb aboard for midgets little people, so a adjustable suspension was installed to allow the tank to lower itself. It was also of the highest importance that even our machines would bow to our Serene Highness. 

    The gun was requested to be of at least 200mm caliber, which our lead engineer said was outrageous (our lead engineer has been REDACTED, and has been replaced by a more suiting, and diverse individual).  Our lead engineer agreed and work began to install the gun. Our female engineers noted that the ammunition was too heavy to be loaded manually for a woman, and was deemed discriminatory, so a autoloader was developed to accommodate the superior gender. 


    As of currently our team failed to meet the deadline and has been REDACTED

    Our team has been sent on a holiday in the North to sunbath in the north. 




    A picture of our team of engineers going to work. 



    All Hail Serene Highness.




    (I will try to add the schematics tomorrow for the suspension and transmission, but it is 01:30 here, and I am taking the bus to work at 06:00. )

  8. On 5/3/2019 at 12:00 AM, Meplat said:

    Does it just come in blue and white with the odd gridded  overlay, or is that just the pilot model?


    Also- Needs more aero/fins.

    Paper panzer, so colors are still being decided upon. 


    Current model aims at a high cd coefficent. 
    A more track orientated model might be developed later. 


    On 5/5/2019 at 6:33 PM, Donward said:

    Hotter take: The Pontiac Aztek was two decades behind its time since all “Crossovers” are simply hatchbacks that people are stupid enough to pay luxury car prices for.

    I never really get why people have this kind of dirty pleasure about Crossovers in my country, or SUVs as they are called here.


    Reasons people state that they like them are:
    1. They have a lot of cargo space.
    2. They have better ground clearance.

    3. They need it go visit their cabin.

    4. They feel they have a better view of the surroundings. 

    5. They like sitting more upright.

    6. They like stepping into the vehicle. 


    1. This is simply not true for 99% of European models.  They are pretty much raised hatchbacks, and actually have smaller cargo space, car manufacturers usually use liters to measure the cargo volume, but because of the taller trunk, the number gets inflated.  Often the station wagon provides equal or more trunk space. 


    2. Again, I have never needed extra ground clearance in my country, even with out sometimes miserable road quality. I even know people that slammed their cars and still got to their cabins in the winter. If it is really important, you can simply buy the off road variant of the station wagon. 


    3. Again a lie, since they have managed to go to their cabins for a few years with their FWD hatchbacks with no problems. Simply learn to not slam the gas pedal and buy proper winter tires and you will have no issues. 4x4 is extremely overrated, especially in most Crossovers. Besides, most, if not all other car models comes with 4x4. 


    4. While true that you can look above some low cars, you will for the most part be just looking at peoples car roofs, instead of their windshields.  This comes at the cost of lower close up visibility, which is so bad in some cases that back up cameras are almost mandatory. 


    5. Though this is person taste, most comfort chairs are more layed back. Like car seats. 


    6. I remember before the crossover thing took off, it was considered a hassle to climb into taller vehicles. 



    For the most part, a off road station wagon should be able to fill in all the above needs, minus sitting upright,  and better vision. 
    It would be cheaper, safer and much better in performance. 


    If you want the taller vehicle with the bigger trunk, buy a MPV, it literally fulfills all the above requirements much better than a crossover. 

    A crossover is typically almost 40% more expensive, weights more, breaks down more often, costs more in maintenance, requires a bigger engine, has worse fuel economy, requires wider tires which causes more road noise and "trailing",  has a higher center of gravity which makes it much more dangerous in accidents and has worse overall close in vision increasing the risk of running over children or hitting small objects. They are usually also sold as a hybrid, making their long range fuel economy even worse, having worse range and poorer towing. 


    If you want a bigger car, buy a bigger car, but don't go around telling bullshit lies because you are too ashamed to admit you want a bigger car. 

  9. On 5/2/2019 at 9:58 AM, Collimatrix said:

    So, for the record, this is how Obus-G works:



    See those little ports at the back end of the shell?  Those let in propellant gas to the inside of the shell, which then vents out the ports in the front and through the gap between the nose fuze and the shell body.  The inner HEAT warhead is "floating" on the high-propellant gas that gets vented inside the shell.

    So it levitates on a cushion of gas? 


    I read something about it on the War Thunder forum that it used bearings. 

    Is the gas used for counteracting the rotation? 




    19 minutes ago, Lord_James said:

    I cannot, for the life of me, find the document about fluid filled armor on this forum, DTIC, or the internet at large. I remember it describes storing fluids (could be fuel, like a gas tank, or something else) in long, thin containers and when struck, the shockwaves from the projectile are transferred through the fluid, reflected off the container walls, and erodes the penetrator via hydrodynamic ram effects by the fluid. 


    The only thing I found on DTIC was a study: 


    Which does remark, in the conclusions, that smaller cavities of fluid (as well as using non-Newtonian fluids) could produce better results. 


    If anyone knows where that study is, I would appreciate it. 


    My my idea is for the side armor around the engine: it would be composed of hexagonal tubes, 50mm between opposing faces, and vertically arranged, so when looking down, it looks like honeycombs. After 2-3 layers, there is a back plate, then a real fuel tank, then the engine. 


    Page 7 SH_MM talks about liquids in armor. The only time I know the forum talked about it. 


    Bronez also links a document:

  10. 1 hour ago, Lord_James said:

    Now that it doesn’t feel like I have an ice pick slowly being pushed into my head, I can elaborate. 


    My engine is closer to the Nomad 2, except the axial compressor is literally the super and turbo chargers. After the compressor, it splits into the ignition air ducts and cooling air ducts. After the cooling air ducts make their way through the engine, they reconnect to the exhaust, then go through the power recovery turbines. 


    The supercharger is used at all speeds, and instead of disconnecting at high speeds, it “shifts down a gear” and acts as a second compressor stage to the turbo. 

    Ah, I see.


    By ignition air, do you mean the air that goes into the cylinder for combustion? 

    And why use air as cooling instead of watercooling? 


    Considering the recovery turbine, I think it could be possible to use a gas turbine for even better power and acceleration, which also doubles as a APU. 

    Water injection is also a alternative. 

  11. F88rPdi.jpg


    Recently was bored one day and drew up a simple car design. 

    For the most part based on the Tesla Model S, Lamborghini Huracan, Mercedes S class and Volvo Polestar 2. 


    The idea was to make a more aerodynamic car, the front is a continuous tear drop shape instead of a notch for the hood. This is possible since its a BEV. 

    The rear is a Kammback to maximize performance and design, while still being practical and not ugly. 

    No side mirrors, just cameras like in the Audi E-tron. 

    It has a low profile (exaggerated in the drawing)  plastic skirt along its bottom, to protect it from rust, with the bumpers made completely out of plastic/glassfiber. 

    Door handles slide into the side when the car comes up to speed, in the case of a power failure, they pop out. 

    It would be flat bottom, with a optional diffuser for better handling, the radiator exhaust if routed down under the car to energize the air, with the help of the Meredith effect.


    Windows, and lights are just there for looks, I am not good at drawing those. 


    Feel free to scrutinize it. 


  12. 18 hours ago, Kal said:

    Magnesium alloy is generally better for welding than aluminium.

    Interesting, I always thought magnesium was very hard to weld.  I guess it stems from the fear of the entire work piece catching fire, even if it is very unlikely. 



    15 hours ago, Lord_James said:

    Pretty sure, the super charger is run via a mechanical system, and the turbocharger is powered by one of the turbo scavengers. 

    Do you use the supercharger as a blower or for better torque and low end RPM? 


    For the compound turbo, is it something like this:


    I suppose that you could have a compound turbo sized so that it spools up at a large way of the rev range. 

    For example. Lets say the tank spends most of its time between 800-1400 RPM, then it would be able to produce enough exhaust gas to power the turbine at roughly 8-900 RPM, and for the higher rev range rarely used, a turbocharger would be employed? 


    So, if I understand the engine correctly, at low RPM, the supercharger would be used to provide power and compression instead of using the crank to compression.  At medium RPM the recovery turbine would have been spooled up to max, and at higher RPM the supercharger would be decoupled by a magnetic clutch or similar and the turbocharger would kick in. 


    Am I correct? or am I completely off?  


    Also, are gas turbine turbochargers allowed, @N-L-M



    Not quite, but it’s not suppose to vary past 1600-1850 rpm. 



    More precise control? Idk

    Well, the thing is, a CVT, is a continuously variable transmission, meaning infinite gears in theory. 

    Which means you can have a gearbox with a ratio of 1 to 20, with anything in between. Like 15, 12, 7, 2, 10,12312321 etc. 


    This means that the engine will always have the appropriate gear ratio for the RPM. No gear selection, just the engine humming happily at its optimal RPM. 

    You can, however have a selector for economy and power. 


    Lets say the engine produces its max power at 3000RPM, but runs the most efficient at 2000RPM, then the transmission would aim to always have the engine at 2000RPM for economy, or 3000 RPm for max power. 

    You should have a "first gear" and reverse gear though, as a conventional CVT provides poor torque initially,  and is incapable of switching direction. 


    It would have 3 gears, first gear, continuous gear and reverse. 



    Love your engine so far btw, certainly a neglected design in the automotive world. 

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